This invention relates to improvements in oil and/or gas well production methods and means and more particularly, but not by way of limitation, to a controlled reservoir production method and means for increasing fluid recovery from a well bore. The method and means described can also be used for leaching or chemical extraction means used in mining or mineral deposit extraction processes.
It is a well known fact that out of the 440 billion barrels of proven oil reserves in the United States only about one-third, or approximately 145 billion barrels, can be produced by normal means. The reason for this low recovery can primarily be attributed to high reservoir capillary forces, high oil viscosity and low reservoir sweep efficiency.
Extensive research has taken place regarding the movement of fluids through subsurface formations or through a medium, and the mechanisms and means required to reduce capillary forces and high oil viscosities. The fluid movement research has concentrated on the ways by which fluids move through various media, the media constraints placed upon the fluids, etc. In the area of capillary forces and high oil viscosities, injection fluids have been developed that can reduce capillary forces and lower high oil viscosities. Despite these efforts and considerable field testing the results of this work have not been very encouraging. Operation efficiencies still remain quite low and the costs quite high. Improving sweep efficiency has been even more difficult to do if one uses conventional well placement techniques. Thus, the means and technology to increase oil recovery from known reservoirs has not significantly improved, nor have the techniques of applying chemical or leaching extraction processes.